I'm looking for a device and don't know what its called...
We've got two batteries on a diesel salt water boat. Looking for something to charge the second battery only after the primary unit is fully charged.
Right now, there is an isolator (which is just a couple large diodes) that appears broken from years of saltwater corrosion. We're looking to replace this. The idea here is to run the starter off one battery and make sure its charged before going to the user battery.